1. Technical Field
The present invention relates to a projector that projects an image on a projection surface using a plurality of light sources and a light emission control method in the projector.
2. Related Art
There has been known a projector that modulates light from a light source on the basis of an input image and projects the light on a screen via a projection lens. It is known that, in the projector, white balance changes because of a change in a characteristic of the light source when the light source is replaced or because of a change in a characteristic (illuminance) of the light source over time. Therefore, there has been proposed a projector having a function of adjusting the white balance of an image actually projected on a screen to an appropriate state (see, for example, JP-A-2006-140839).
There has been known a projector including a light source that can adjust luminance through PWM (pulse width modulation) control such as an LED or a laser (see, for example, JP-A-2010-051068).
In a projector including a plurality of light sources, optical outputs of the light sources are not always uniform and paces of aged deterioration of the light sources are not always uniform either. When a state of an optical system changes, white balance sometimes changes because, for example, optical path lengths from the light sources to the focus of a lens are different. In this way, in the projector including the plurality of light sources, white balance changes in a complicated manner. If the white balance of an image projected on a screen is actually measured and adjusted every time the white balance changes, the white balance is frequently adjusted and the adjustment takes time.